Installing insulation against the walls and foundations of building structures is well known in the art. Insulation is used to hold heat within a building thereby making heating systems more efficient while at the same time preventing moisture from damaging the walls of a structure. In many communities, below-grade insulation is required by local building code.
At present, prior to pouring concrete walls, vertical forms, most typically comprised of plywood sheets, are positioned in parallel, opposing pairs to form an interior cavity into which the fluid concrete is poured. The forms are held in the fixed vertical orientation during the pouring process by form ties, which are most typically of metal. These ties extend between the forms within the interior cavity and then through each of the forms to the exterior of the forms where a cross-member is placed into the tie to prevent the forms from moving outwardly. Once a poured-concrete wall has cured sufficiently, the forms are removed, leaving embedded within the wall, metal wall ties. In present usage, the portion of the wall ties extending out from the surface of the wall presents a surface discontinuity which makes the flush installation of a sheet of insulation to the wall surface impossible. The portion of the tie extending out from the wall must be removed. The removal is accomplished by a general laborer using a tool specially designed for removal of the tie. The tool is slid over the tie to a point where the tool envelopes the entire portion of the tie to be removed, then the tool is rotated snapping the metal tie nearly flush with the surface of the wall. This procedure is carried out one tie at a time, one side at a time. The removal process thus results in the incurrence of capital expenses for the tool and labor costs for its use.
After removal of the exposed portions of the ties, sheathing in the form of sheets of insulation is positioned against the relatively smooth walls. Most of the insulation and the portion of the wall to which the insulation is attached is then buried in a backfill operation. To hold the sheathing in place during the backfill operation, prior to backfilling, metal tacks or bolts are shot through the sheathing into the concrete by means of an explosive-charge delivered by a specially designed gun. The tacking operation involves additional costs for materials and labor. Moreover, the existing method involves safety risks through malfunction or improper use of the explosive-charge gun, and through the creation of shards as the metal contacts the hardened concrete.
A device and method for applying and retaining insulating sheathing to a poured concrete wall without the need to remove the ties originally imbedded in the wall and without the need to drive metal pieces into hardened concrete, would be an important improvement in the art.